The Secret Life of Horseradish

The rough-and-ready horseradish plant has long been snubbed by prudent farmers and gardeners. The perennial horseradish (Armoracia lapathifolia) grows wildly throughout temperate climates, leading many people to consider it just another pesky weed. In fact, the plant is so tough that great efforts have been made to limit its growth. Only sauce and Bloody Mary lovers hold horseradish relish in admiration for its spicy properties. Yet the plant lives a double life that few may realize.

The minced root has another use: as a decontaminate of industrial waste water, according to a recent study at Pennsylvania State University that has received a $450,000 grant from the Environmental Protection Agency.

Horseradish can detoxify the harmful water more efficiently than chemical treatments, says Jerzy Dec, a re search associate at Penn State's Center for Bioremediation and Detoxification, and it is "100 percent" cleaned after contact with the plant. The otherwise considerable expense of decontaminating the water also drops, making a horseradish treatment appealing to those concerned with the bottom line as well as the land. It can illustrate to both industry and consumers that a natural alternative to the waste water dilemma can be the best one.

The secret of the plant's strength against all sorts of toxins is the enzyme peroxidase. The plant's rigid tissue stabilizes the enzyme, and traps it for use. Then the active element of the horseradish simply and swiftly cancels out the pollutant's presence in the water.

The application process is also surprisingly simple. The horseradish is harvested in tons; then the root is separated from the rest of the bushy plant and minced thoroughly. The horseradish and a proportionate amount of hydrogen peroxide are then added to the polluted water. In half an hour, the pollutants are neutralized, forming insoluble polymers which can be easily filtered from the water.

Horseradish is most powerful against phenols, a group of chemicals considered a prime pollutant of industrial water. Phenols are produced in most major American industries, such as steel and iron manufacturing, paper bleaching, coal conversion, ore mining, and in the production of dyes, plastics, and pesticides. Horseradish can treat 50 different phenols in various ways, and a few other chemicals to boot.

The plant could be practically invaluable in the event of a water crisis as well. "In case of a disaster," says Dec, "any other method would demand complex preparations, but here you just dump a ton of horseradish and add it to the lake or river and get it decontaminated."

The same horseradish can even be used again, with the same purifying effects as when it was freshly minced. The root's power remains for up to 30 treatments of toxic water.

Anyone who has attempted to thwart an invasion of horseradish in their garden understands the economy of growing the plant in volume. It grows at such a rate that it has cost more to limit the proliferation of horseradish than it ever would to let it grow as it chooses. It needs very little attention, and can be produced in massive amounts for a very low cost. It needs no preparation other than mincing, and the only by-product of the purification process is the spent horseradish instead of the many equally destructive chemicals left over after traditional purification. In comparison to chemical treatments that cost millions of dollars a day, the university estimates that the horseradish would cost only $920 per day to treat 66,000 gallons of phenol-contaminated water.

There is no news just yet on whether or not horseradish can be used to purify water in the home, yet the massive amount of waste water that could be treated by the plant industrially sets the stage for other vegetable/organic alternatives to water decontamination.

Dr. Jean-Marc Bollang, of Penn State's College of Agricultural Science, found that other plants may have similar decontaminating properties. Purification by potatoes and radishes may be next, though potatoes don't hold up as well as the mighty horseradish under repeated use.

The German Postal Service Electrified

Neither snow nor rain nor energy crisis stays the German Postal Service from the completion of their rounds. This summer, Germany's mail couriers will become leaders in the transportation revolution, taking to streets in electric fleets. Mail delivery and the electric battery will meet in the largest-ever use of electricity powered, zero-emissions vehicles.

The German Postal Service (Deutsche Bundepost Postdienst) will be the first to attempt a widespread use of electric vehicles to deliver mail in place of fossil fuel—dependent and pollution—causing—vehicles. Over 50 vans and pick-up trucks will be powered by the Electric Fuel system, transporting mail throughout several German municipalities.

The battery functions by a "zinc-air" system, according to Robert Ehrlich, CEO of Electric Fuel, the company with the contract to provide the postal service with the batteries Electric Fuel developed and manufactures.

"It is very simple," he says. Zinc anodes, which conduct the negatively charged side of a battery, are placed on a metal frame. Air is forced through the anode, producing a catalytic reaction that results in an oxygen ion which, combined with zinc, produces the positive electrical charge.

The zinc-air battery produces no emissions, says Ehrlich, and is built with completely non-toxic materials. It is also easily recycled. One moderately benign by-product of the system is the small amount of carbon dioxide released during the charging process, however.

The cassettes are recharged and reinserted into the vehicle after a brief trip to an automated regeneration facility. Machines at the electric fueling headquarters, to be built in Bremen, Germany, will be operated by the city's utility company.

The battery is relatively lightweight, allowing for a greater conservation of electricity by the vehicle when it is in use. Weighing in at only 1,666 pounds, the battery is less than 22 percent of the German Postal Service vehicles's gross weight. With the system installed, the vehicles can carry over 1.1 tons, and travel at speeds of over 75 mph.

In the past, widespread use of electric batteries in place of traditional fuels was impractical for many drivers. The earlier batteries could only power lightweight vehicles, and would hold a charge for a short amount of time. Electric cars could travel for only short distances, and were not considered a practical alternative for everyday transportation. The refueling process even took eight hours.

In a test at Electric Fuel's facilities in Ontario last December, a vehicle powered by the zinc-air battery ran at a constant speed of 40 mph for over 10 hours on a single charge, claims CEO Ehrlich—over 400 miles on one fuel-up. The battery is designed to contain the same amount of energy held in a traditional fuel tank, making it possible for the vehicle to drive as far as it would have on a full tank of gas. That ability has long eluded battery manufacturers.

The postal service should be outfitted in electric-battery—powered vans and lightweight pick-up trucks by this summer, the date scheduled for the completion of the regeneration facilities. The vehicles will be on the road and delivering mail to Germany until the end of 1996, when the battery system will be analyzed.

And if all goes well, 40,000 new vehicles throughout the Postdienst and the Bundepost Telekoms will be electrified.